Ehlers-Danlos Syndrome: What Is It and How Is It Treated?

Ehlers-Danlos syndrome (EDS) is an inherited condition that affects the connective tissues in the body. Connective tissue is responsible for supporting and structuring the skin, blood vessels, bones, and organs. It’s made up of cells, fibrous material, and a protein called collagen. A group of genetic disorders cause Ehlers-Danlos syndrome, which results in a defect in collagen production.

Recently, 13 major types of Ehlers-Danlos syndrome have been subtyped. These include:

classic

classic-like

cardiac-valvular

vascular

hypermobile

arthrochalasia

dermatosparaxis

kyphoscoliotic

brittle cornea

spondylodysplastic

musculocontractural

myopathic

periodontal

Each type of EDS affects different areas of the body. However, all types of EDS have one thing in common: hypermobility. Hypermobility is an unusually large range of movement in the joints.

According to the National Library of Medicine’s Genetics Home Reference, EDS affects 1 in 5,000 people worldwide. Hypermobility and classic types of Ehlers-Danlos syndrome are the most common. The other types are rare. For example, dermatosparaxis affects only about 12 children worldwide.

In most cases EDS is an inherited condition. The minority of cases are not inherited. This means that they occur via spontaneous gene mutations. Defects in the genes weaken the process and formation of collagen.

All of the genes listed below provide instructions on how to assemble collagen, except for ADAMTS2. That gene provides instructions for making the proteins that work with collagen. The genes that can cause EDS, while not a complete list, include:

Parents are sometimes silent carriers of the defective genes that cause EDS. This means the parents may not have any symptoms of the condition. And they’re unaware they’re carriers of a defective gene. Other times, the gene cause is dominant and can cause symptoms.

Symptoms of vascular EDS

Doctors may use a series of tests to diagnose EDS (except for hEDS), or rule out other similar conditions. These tests include genetic tests, skin biopsy, and echocardiogram. An echocardiogram uses sound waves to create moving images of the heart. This will show the doctor if there are any abnormalities present.

A blood sample is taken from your arm and tested for mutations in certain genes. A skin biopsy is used to check for signs of abnormalities in collagen production. This involves removing a small sample of skin and checking it under a microscope.

A DNA test can also confirm if a defective gene is present in an embryo. This form of testing is done when a woman’s eggs are fertilized outside of her body (in vitro fertilization).